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81.
Brucella lumazine synthase elicits a mixed Th1-Th2 immune response and reduces infection in mice challenged with Brucella abortus 544 independently of the adjuvant formulation used 总被引:5,自引:0,他引:5 下载免费PDF全文
Velikovsky CA Goldbaum FA Cassataro J Estein S Bowden RA Bruno L Fossati CA Giambartolomei GH 《Infection and immunity》2003,71(10):5750-5755
The immunogenicity and protective efficacy of recombinant lumazine synthase from Brucella spp. (rBLS) administered with different adjuvants was evaluated in mice. Mice were immunized with rBLS in the absence or the presence of aluminum hydroxide gel (BLS-Al), monophosphoryl lipid A (BLS-MPA), or incomplete Freund's adjuvant (BLS-IFA). rBLS per se induced a vigorous immunoglobulin G (IgG) response, with high titers of IgG1 as well as IgG2. All the adjuvants increased this response; the BLS-IFA formulation was the most effective at inducing BLS-specific IgG antibodies. In addition, after in vitro stimulation with rBLS, spleen cells from BLS-IFA-, BLS-Al-, or BLS-MPA-immunized mice proliferated and produced interleukin-2 (IL-2), gamma interferon (IFN-gamma), IL-10, and IL-4, suggesting the induction of a mixed Th1-Th2 response. Immunization with rBLS protected mice against challenge with B. abortus 544. The levels of protection in the spleen were similar for all adjuvants, but only BLS-Al and BLS-IFA were effective in the liver. Our results indicate that BLS might be a useful candidate for the development of subunit vaccines against brucellosis, since it elicits antigen-specific cellular responses, with production of IFN-gamma and protection, independently of the adjuvant formulation used. 相似文献
82.
Impaired hair follicle morphogenesis and cycling with abnormal epidermal differentiation in nackt mice,a cathepsin L-deficient mutation 总被引:1,自引:0,他引:1 下载免费PDF全文
Benavides F Starost MF Flores M Gimenez-Conti IB Guénet JL Conti CJ 《The American journal of pathology》2002,161(2):693-703
We previously described an autosomal-recessive mutation named nackt (nkt) exhibiting partial alopecia associated with CD4(+) T-cell deficiency. Also, we recently reported that nkt (now Ctsl(nkt)) comprises a deletion in the cathepsin L (Ctsl) gene. Another recent study reported that Ctsl knockout mice have CD4(+) T-cell deficiency and periodic shedding of hair, which recapitulate the nkt mutation and the old furless (fs) mutation. The current study focuses on the dermatological aspects of the nkt mutation. Careful histological analysis of skin development of homozygous nkt mice revealed a delayed hair follicle morphogenesis and late onset of the first catagen stage. The skin of Ctsl(nkt)/Ctsl(nkt) mice showed mild epidermal hyperplasia and hyperkeratosis, severe hyperplasia of the sebaceous glands, and structural alterations of hair follicles. Epidermal differentiation seems to be affected in nkt skin, with overexpression of involucrin and profilaggrin/filaggrin along with focal areas of keratin 6 expression in the interfollicular epidermis. Severe epidermal hyperplasia, acanthosis, orthokeratosis, and hyperkeratosis were only observed in mice maintained in nonpathogen-free environments. The analysis of Rag2-/- Ctsl(nkt)/Ctsl(nkt) double-mutant mice indicates that the skin defect remains under the absence of T and B cells. This animal model provides in vivo evidence that cysteine protease cathepsin L plays a critical role in hair follicle morphogenesis and cycling, as well as epidermal differentiation. 相似文献
83.
D S Colombari E Colombari W A Saad L A Camargo A Renzi L A De Luca Júnior J V Menani 《Neuroscience letters》1992,143(1-2):255-258
The present study was performed to investigate the effect of treatment with furosemide on the pressor response induced by intracerebroventricular (i.c.v.) injections of cholinergic (carbachol) and adrenergic (norepinephrine) agonists, angiotensin II (ANGII) and hypertonic saline (HS, 2 M NaCl). The changes induced by furosemide treatment on the pressor response to intravenous (i.v.) norepinephrine, ANGII and arginine vasopressin (AVP) were also studied. Rats with a stainless-steel cannula implanted into the lateral ventricle (LV) were used. Two injections of furosemide (30 mg/kg b.wt. each) were performed 12 and 1 h before the experiments. Treatment with furosemide reduced the pressor response induced by carbachol, norepinephrine and ANGII i.c.v., but no change was observed in the pressor response to i.c.v. 2 M NaCl. The pressor response to i.v. ANGII and norepinephrine, but not AVP, was also reduced after treatment with furosemide. These results show that the treatment with furosemide impairs the pressor responses induced by central or peripheral administration of adrenergic agonist or ANGII, as well as those induced by central cholinergic activation. The results suggest that the treatment with furosemide impairs central and peripheral pressor responses mediated by sympathetic activation and ANGII, but not those produced by AVP. 相似文献
84.
Allele-Specific PCR Method Based on pncA and oxyR Sequences for Distinguishing Mycobacterium bovis from Mycobacterium tuberculosis: Intraspecific M. bovis pncA Sequence Polymorphism 总被引:1,自引:0,他引:1 下载免费PDF全文
Luz Elena Espinosa de los Monteros Juan Carlos Galn Montserrat Gutirrez Sofía Samper Juan F. García Marín Carlos Martín Lucas Domínguez Luis de Rafael Fernando Baquero Enrique Gmez-Mampaso Jesús Blzquez 《Journal of clinical microbiology》1998,36(1):239-242
An allele-specific amplification method based on two genetic polymorphisms to differentiate Mycobacterium tuberculosis from Mycobacterium bovis was tested. Based on the differences found at position 169 in the pncA genes from M. tuberculosis and M. bovis, a PCR system which was able to differentiate most of the 237 M. tuberculosis complex isolates tested in one of the two species was developed. All 121 M. tuberculosis strains showed the expected base (cytosine) at position 169. Most of the M. bovis isolates had a guanine at the cited position. Nevertheless, 18 of the 116 M. bovis isolates, all of them goat isolates, showed the pncA polymorphism specific to M. tuberculosis. These results suggest that goat M. bovis may be the nicotinamidase-missing link at the origin of the M. tuberculosis species. Based on the polymorphism found at position 285 in the oxyR gene, the same system was used to differentiate M. tuberculosis from M. bovis. In this case, DNAs from all 121 M. tuberculosis isolates had the expected base (guanine) at this position. In addition, all 116 M. bovis isolates, including those from goats, showed the identical polymorphism (adenine). The oxyR allele-specific amplification method can differentiate M. bovis from M. tuberculosis, is rapid (results can be obtained in less than 3 h), and is easy to perform. 相似文献
85.
Antonio López-Beltrán Alfonso S. Calañas Pilar Jimena Alberto L. Escudero Telma R. Campello Manuel Muñoz-Torres Fernando Escobar-Jiménez Rafael E. Carvia F. F. Nogales 《Virchows Archiv : an international journal of pathology》1997,431(2):149-151
Three further cases of mature benign cystic teratomas of the ovary associated with virilization are added to the three previously
reported in the literature. They were found in postmenopausal, obese, diabetic women aged 52, 61, and 67 years. The patients
presented with hirsutism and voice changes and clitoromegaly was present in one. Testosterone and androstenedione levels were
elevated but promptly regressed after removal of the tumours. Histologically, sheets of stromal luteinized cells were found
peripherally at the interface between the neoplasm and ovarian tissue. Luteinization of ovarian stroma induced by an unknown
factor related to diabetes mellitus is the origin of the virilization.
Received: 8 January 1997 / Accepted: 28 February 1997 相似文献
86.
Haley Kaplowitz Reynaldo Martorell Fernando S. Mendoza 《American journal of human biology》1989,1(5):631-648
Mexican-American children are shorter but relatively heavier than non-Hispanic white children. The excess relative weight is probably due to increased fat rather than lean body mass and, more specifically, to increased fat deposition on the upper trunk sites. The objective of this paper is to describe the level of fatness and fat distribution in a large, representative sample of Mexican- American children and adolescents from the recently completed Hispanic Health and Nutrition Examination Survey (HHANES). As expected, Mexican-American children are generally fatter than white children measured in previous national surveys (National Health and Nutrition Examination Survey [NHANES] II, Health Examination Survey [HES]). Differences are particularly evident for trunk skinfold thicknesses and generally increase with age. Indices of fat distribution clearly show a centralized, upper body adiposity pattern among Mexican-Americans, a cause for concern since greater fat deposition on the trunk has been associated with increased risk of certain chronic disease. 相似文献
87.
Rotavirus diarrhea severity is related to the VP4 type in Mexican children 总被引:6,自引:0,他引:6 下载免费PDF全文
Mota-Hernández F Calva JJ Gutiérrez-Camacho C Villa-Contreras S Arias CF Padilla-Noriega L Guiscafré-Gallardo H de Lourdes Guerrero M López S Muñoz O Contreras JF Cedillo R Herrera I Puerto FI 《Journal of clinical microbiology》2003,41(7):3158-3162
This report is of a community-based case control study to assess whether the severity of acute diarrhea by rotavirus (RV) in young children is associated with a particular VP7 (G) or VP4 (P) RV serotype. Five hundred twenty children younger than 2 years of age with diarrhea lasting less than 3 days were age and gender matched with 520 children with no diarrhea. The G and P serotypes were determined with specific monoclonal antibodies, and the VP4 serotype specificity in a subgroup was confirmed by genotyping. Infection with a G3 serotype led to a higher risk of diarrhea than infection with a G1 serotype. Infection with a G3-nontypeable-P serotype was associated with more severe gastroenteritis than infection with a G3 (or G1) P1A[8] serotype. A child with diarrhea-associated dehydration was almost five times more likely to be infected with a G3-nontypeable-P serotype than a child without dehydration (P < 0.001). Moreover, the two predominant monotypes within serotype P1A[8] had significantly different clinical manifestations. In this study, the severity of RV-associated diarrhea was related to different P serotypes rather than to G serotypes. The relationship between serotype and clinical outcomes seems to be complex and to vary among different geographic areas. 相似文献
88.
Morphologic Study of the Participation of the Complement System in Hyperacute Rejection of Renal Xenotransplants 下载免费PDF全文
Jaime E. Mej¯a-Laguna Adolfo Mart¯nez-Palomo Carlos E. Biro Bibiana Ch¬vez Fernando LÌpez-Soriano Marcelo Garc¯a-Cornejo 《The American journal of pathology》1972,69(1):71-78
The role of polymorphonuclear leukocyte (PMN) and platelet infiltration in the hyperacute rejection of renal xenotransplants was studied. In a first group, a dog kidney was grafted to rabbit recipients with intact immune adherence and chemotaxis. A second group included recipients depleted of PMN's with nitrogen mustard, and in a third group, immune adherence and chemotaxis were modified by depleting the third component of complement by means of cobra venom factor. Serial kidney biopsies were studied with light and electron microscopic technics. A semiquantitative evaluation of PMN and platelet glomerular infiltration indicated that a reduction in the number of PMN's or platelets is associated with an increased survival time of the transplanted kidney. 相似文献
89.
Safety and immunogenicity of a prototype enterotoxigenic Escherichia coli vaccine administered transcutaneously 总被引:3,自引:0,他引:3 下载免费PDF全文
Güereña-Burgueño F Hall ER Taylor DN Cassels FJ Scott DA Wolf MK Roberts ZJ Nesterova GV Alving CR Glenn GM 《Infection and immunity》2002,70(4):1874-1880
Transcutaneous immunization (TCI) is a new method for vaccine delivery that has been shown to induce immunity relevant to enteric disease vaccines. We evaluated the clinical safety and immunogenicity of a recombinant subunit vaccine against enterotoxigenic Escherichia coli (ETEC) delivered by TCI. Adult volunteers received patches containing the recombinant ETEC colonization factor CS6, either with heat-labile enterotoxin (LT) or patches containing CS6 alone. The vaccine was administered at 0, 1, and 3 months, and serum antibodies and antibody-secreting cells (ASCs) were assessed. Among the 26 volunteers that completed the trial, there were no responses to CS6 in the absence of LT. In the groups receiving both CS6 and LT, 68 and 53% were found to have serum anti-CS6 immunoglobulin G (IgG) and IgA, respectively; 37 and 42% had IgG and IgA anti-CS6 ASCs. All of the volunteers receiving LT had anti-LT IgG, and 90% had serum anti-LT IgA; 79 and 37% had anti-LT IgG and IgA ASCs. Delayed-type hypersensitivity (DTH), suggesting T-cell responses, was seen in 14 of 19 volunteers receiving LT and CS6; no DTH was seen in subjects receiving CS6 alone. This study demonstrated that protein antigens delivered by a simple patch could induce significant systemic immune responses but only in the presence of an adjuvant such as LT. The data suggest that an ETEC vaccine for travelers delivered by a patch may be a viable approach worthy of further evaluation. 相似文献
90.
Fernando Gabriel Chirdo María Cristina Añón Carlos Alberto Fossati 《Food and Agricultural Immunology》1998,10(2):143-155
Optimization of three enzyme immunoassays of very high sensitivity using three antiprolamin monoclonal antibodies (MAbs) (13B4, 11C4 and 12A1) is presented here. These MAbs are specific for those prolamins toxic for coeliac patients, as determined by immunoblotting analysis. Biotinylated MAbs were used in two of the assays. In a competitive ELISA, the binding of each biotinylated MAb to a gliadin‐coated solid phase was inhibited by gliadin in the fluid phase. The best result was obtained using the biotinylated MAbl3B4 (detection limit: 20 ng ml?1). With regard to capture ELISA, we tested the performance of the three MAbs. In this sandwich ELISA, the MAb used for antigenic capture was the same as that used as secondary biotinylated antibody. The MAbl2Al had the best performance (detection limit: 1 ng ml?1). The use of biotin‐labelled gliadin in a quantitative immunoassay with a detection limit of 5 ng ml?1 is also reported. This assay involves an antigenic capture using the MAbl2Al followed by a competition between biotinylated and non‐biotinylated gliadin. We have found the use of the streptavidin‐biotin interaction as signal amplification system to be very useful. This technique, as far as we know, has not been previously reported for gliadin quantification. 相似文献